/**
 * WP Multi Wiki – TOC Script
 * Highlights active TOC entry while scrolling + toggle functionality.
 */
(function () {
  'use strict';

  document.addEventListener('DOMContentLoaded', function () {
    var toc = document.getElementById('wmw-toc');
    if (!toc) return;

    // ── Toggle ────────────────────────────────────────────────────────────
    var toggleBtn = toc.querySelector('.wmw-toc-toggle');
    var tocList   = document.getElementById('wmw-toc-list');
    if (toggleBtn && tocList) {
      toggleBtn.addEventListener('click', function () {
        var expanded = toggleBtn.getAttribute('aria-expanded') === 'true';
        toggleBtn.setAttribute('aria-expanded', String(!expanded));
        tocList.style.display = expanded ? 'none' : '';
        var icon = toggleBtn.querySelector('.wmw-toc-toggle-icon');
        if (icon) icon.innerHTML = expanded ? '▶' : '▼';
      });
    }

    // ── Active Highlight on Scroll ────────────────────────────────────────
    var links    = toc.querySelectorAll('a[href^="#"]');
    if (!links.length) return;

    var headings = [];
    links.forEach(function (link) {
      var id = link.getAttribute('href').substring(1);
      var el = document.getElementById(id);
      if (el) headings.push({ el: el, link: link });
    });

    function setActive() {
      var scrollY   = window.scrollY || window.pageYOffset;
      var offset    = 80; // sticky header offset
      var activeIdx = -1;

      headings.forEach(function (h, i) {
        if (h.el.getBoundingClientRect().top + scrollY - offset <= scrollY) {
          activeIdx = i;
        }
      });

      links.forEach(function (l) { l.classList.remove('wmw-toc-active'); });
      if (activeIdx >= 0) {
        headings[activeIdx].link.classList.add('wmw-toc-active');
      }
    }

    var ticking = false;
    window.addEventListener('scroll', function () {
      if (!ticking) {
        requestAnimationFrame(function () {
          setActive();
          ticking = false;
        });
        ticking = true;
      }
    }, { passive: true });

    setActive(); // run once on load

    // ── Sidebar: mark current article ────────────────────────────────────
    var currentUrl = window.location.href.replace(/\/$/, '');
    document.querySelectorAll('.wmw-sidebar .wmw-article-list a').forEach(function (a) {
      if (a.href.replace(/\/$/, '') === currentUrl) {
        a.classList.add('wmw-current');
        // Scroll link into view inside sidebar
        var sidebar = document.getElementById('wmw-sidebar');
        if (sidebar) {
          var linkTop = a.offsetTop;
          sidebar.scrollTop = linkTop - 80;
        }
      }
    });
  });
})();